The discussion of documents, deeds, materials, devices, papers and the like is only incorporated in this specification to provide some context for the present invention. These materials shall not be deemed or intended to be wholly or partially part of the prior art, or to be of general knowledge in the field of the present invention, as existing before the priority date of any claim of this application.
WO03/066467, for instance, discloses a closure assembly for pharmaceutical applications which has both tamper evident and child proof features: the tamper evident feature is provided by a first portion of the outer surface of the closure assembly, which creates a step with respect to a second portion of the same outer surface, whereas the child proof feature is provided by forcing the user to an opening movement that shall necessarily involve two distinct directions. This closure assembly has the undoubted drawback of simple opening, which is inherently disadvantageous in the pharmaceutical field, that requires child proof closure assemblies.
WO2005/021400, by Guala Closures S.p.A. discloses a tamper evident closure assembly that is opened by a movement that shall not necessarily involve two distinct directions (hence defining a non child proof closure), in which an internal element is broken and moved to expose a surface underneath it, to show that first opening has occurred. The main drawback of this closure assembly consists in the need for internal breakable elements as well as a relatively complex system for breaking them.
EP1511677B1, granted to Guala Closures UK Limited discloses a tamper evident closure assembly, in which the opening movement exposes a counteracting annular element, the closure of the closure element being unable to be restored to the starting position after first opening. Nevertheless, the simple construction of the structure of this closure unit is a limit to tamper evident features, which necessarily rely on the size of the annular element to be exposed during first opening.
The above discussion of the prior art shows that there is still a need for a closure assembly that can combine both features of simple construction and effectiveness of the above described tamper evident systems.
In view of the above prior art, the object of the present invention is to at least partially fulfill the above need, while at least partially obviating prior art drawbacks.
Furthermore, the present invention provides a closure assembly having advantages in terms of simple fabrication, greater strength, more compact design and/or higher versatility.